How to create a simple invoice

A simple invoice needs a clear who-bills-whom header, at least one line item, and a total you can defend. On this site, invoice #INV-1042 dated 2026-10-06 with one line of quantity 8 at unit price 75, tax 0%, and discount 0%, totals 600 from the invoice generator. Those figures match the calculator used by the preview.

What to fill in

1. Business details: your name or company, address, contact.
2. Client details: who pays.
3. Invoice number and date: use a scheme you can search later (INV-1042, 2026-10-06).
4. Line items: description, quantity, unit price.
5. Tax and discount: leave at zero for the worked example; raise them when your contract needs them.
6. Currency: one code for the whole document.
7. Preview and PDF: check the layout, then export.

Drafts autosave in localStorage on your device. Clearing site data clears drafts.

Line math

With tax and discount at zero, line total = quantity × unit price.

When both percents are on, the calculator applies the discount percent first, then tax on the reduced amount. That order matters for the grand total.

Build the worked example

1. Open the invoice generator.
2. Set the invoice number to INV-1042 and the date to 2026-10-06 (or today’s date if you are practicing).
3. Add one line: description such as “Consulting hours”, quantity 8, unit price 75.
4. Leave tax and discount at 0.
5. Confirm subtotal and grand total show 600.
6. Preview, then download the PDF.

If you need a foreign currency on the document, convert the quote first, then type the agreed unit prices. The invoice tool will not rewrite lines when you change the currency label. That workflow is covered in how to make an invoice in multiple currencies.

What the tool does not do

It does not fetch live exchange rates. It does not store your PDF on a Numbrixiya server. It does not decide VAT treatment for your country. It does not replace accounting software for books and filing. Use it to produce a clean PDF from numbers you already agreed.

Add more lines when the job has several deliverables. Keep descriptions specific enough that a client can match the line to the work. Re-check the preview after you change tax or discount so the PDF matches the on-screen totals.

For the worked example, resisting the urge to add decorative tax “for looks” keeps the arithmetic obvious: eight times seventy-five is six hundred with no extra steps. When you later add a real tax percent, change one field at a time and watch discount-before-tax behavior on that line before you send the file.

Checklist before you send the PDF

• Invoice number is unique in your records.
• Date matches the agreement or delivery date your client expects.
• Quantity and unit price match the quote.
• Currency code matches the money you expect to receive.
• Tax and discount percents match the contract (zero in the worked example).
• Preview shows the same grand total you will cite in email.

If any line fails that check, fix it in the form and export again. Do not edit the PDF by hand in a way that drifts from the calculator total. Keeping the PDF and the on-screen grand total identical avoids awkward “which number is right?” threads with the client.

Try it

Enter the one-line example and confirm a grand total of 600 before you export.